Astronomers say they've found oldest galaxy so far

View full sizeAP Photo/NASAThis undated handout image provided by NASA, taken by the Hubble Space Telescope, shows a small smudge, center, that astronomers believe is the oldest thing they have ever seen, with light from a long time ago in a galaxy far, far away.

WASHINGTON (AP) — Astronomers believe they've found the oldest
thing they've ever seen in the universe: It's a galaxy far, far away
from a time long, long ago.

Hidden in a Hubble Space Telescope
photo released earlier this year is a small smudge of light that
European astronomers now calculate is a galaxy from 13.1 billion years
ago. That's a time when the universe was very young, just shy of 600
million years old. That would make it the earliest and most distant
galaxy seen so far.

By now the galaxy is so ancient it probably
doesn't exist in its earlier form and has already merged into bigger
neighbors, said Matthew Lehnert of the Paris Observatory, lead author of
the study published online Wednesday in the journal Nature.

"We're
looking at the universe when it was a 20th of its current age," said
California Institute of Technology astronomy professor Richard Ellis,
who wasn't part of the discovery team. "In human terms, we're looking at
a 4-year-old boy in the life span of an adult."

While Ellis finds
the basis for the study "pretty good," there have been other claims
about the age of distant space objects that have not held up to
scrutiny. And some experts have questions about this one. But even the
skeptics praised the study as important and interesting.

The
European astronomers calculated the age after 16 hours of observations
from a telescope in Chile that looked at light signatures of cooling
hydrogen gas.

Earlier this year, astronomers had made a general
estimate of 600 to 800 million years after the Big Bang for the most
distant fuzzy points of light in the Hubble photograph, which was
presented at an astronomy meeting back in January.

In the new
study, researchers focused on a single galaxy in their analysis of
hydrogen's light signature, further pinpointing the age. Garth
Illingworth of the University of California, Santa Cruz, who was the
scientist behind the Hubble image, said it provides confirmation for the
age using a different method, something he called amazing "for such
faint objects."

The new galaxy doesn't have a name — just a series
of letters and numbers. So Lehnert said he and colleagues have called
it "the high red-shift blob. "Because it takes so long for the light to
travel such a vast time and distance, astronomers are seeing what the
galaxy looked like 13.1 billion years ago at a time when it was quite
young — maybe even as young as 100 million years old — Lehnert said. It
has very little of the carbon or metal that we see in more mature stars
and is full of young, blue massive stars, he said.

What's most
interesting to astronomers is that this finding fits with theories about
when the first stars and galaxies were born. This galaxy would have
formed not too soon after them.

"We're looking almost to the edge,
almost within 100 million years of seeing the very first objects,"
Ellis said. "One hundred million years to a human seems an awful long
time, but in astronomical time periods, that's nothing compared to the
life of the stars."